Engines mounted in various vehicles are divided into a gasoline engine, a diesel engine, and an LPG engine according to use fuel.
Further, the vehicle includes a fuel tank for supplying fuel to an engine and a fuel pump module for forcibly supplying the fuel in the fuel tank to an engine.
Generally, as shown in FIGS. 1 and 2, the fuel pump module is configured to include a flange assembly 10, a reservoir body assembly 20, a guide rod 25 connecting the flange assembly 10 with the reservoir body assembly 20, a spring 26 disposed at outside of the guide rod 25, a filter 28 for removing foreign objects included the fuel, and a fuel pump 27 for forced circulation.
This structure can be confirmed through Korean Utility Model Application No. 20-1997-0016877 (Utility Model Registration No. 20-0160774), or the like.
In most cases, the flange assembly 10 is fixed to an inlet part of the fuel tank and the reservoir body assembly 20 is disposed at a bottom of the tank.
In addition, the guide rod 25, which connects the flange assembly with the reservoir body assembly while guiding a motion of the spring, is formed to be slid inwardly of the reservoir body assembly.
In addition, the spring 26 is disposed at the outside of the guide rod 25 and is disposed between the flange assembly and the reservoir body assembly so that the reservoir body assembly is disposed at the bottom of the fuel tank at all times.
The diesel engine, which is an engine that uses the diesel fuel such as diesel oil to generate an output, cannot smoothly supply fuel in a low-temperature region below zero even though the vehicle has the above-mentioned fuel pump module for forcibly supplying the fuel.
That is, the diesel fuel such as diesel oil, or the like, becomes clotted and crystallized in a paraffin form even in the low-temperature region (usually, a temperature region below zero), or the like, and thus, cannot be easily supplied through the fuel pump module. Therefore, starting performance of the diesel engine may be poor in the low-temperature region below zero and a driving of the engine may not be smoothly performed.